<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
         * {
            margin: 0;
            padding: 0;
        }
        body {
            background: #ddd;
        }
        .canvas1,.canvas2,.canvas3{
                    background-color: #fff;
                    margin-bottom: 10px;
                }
        .wrap {
            padding: 20px;
        }

    </style>
</head>
<body>
    <div class="wrap">
        <div class="box">
          <canvas class="canvas1"></canvas>
          <canvas class="canvas2"></canvas>
          <canvas class="canvas3"></canvas>
        </div>
      </div>
    
    <script src="./js/common.js"> </script>
</body>
</html>